1. Field of the Invention
The present invention involves the optical disk position detection device of an optical disk playing device, specifically involves an optical disk loading final position detection device which detects whether the center of an optical disk of big or small diameter inserted from the insertion inlet is transported to the position in accord with the center of the plummer or not.
2. Description of the Related Art
The Japanese patent application with the publication number of 2006-302476 disclosed an optical disk loading final position detection device, which can detect whether the center of an optical disk of big or small diameter is transported to the position in accord with the center of the plummer or not. The optical disk loading final position detection device has the following structure: a delivery roll is located at the optical disk insertion inlet; an optical disk guiding device is located at the position opposite to the delivery roll; a pair of detection bars are provided, which have detection parts contacting the periphery of the optical disks of big diameter or small diameter inserted from the insertion inlet, and the detection parts rotate towards the direction away from the optical disk insertion path; a trigger bar is provided, and as the optical disk is held by the delivery roll and transported by the rotating of the delivery roll, when the center of the optical disk approaches the center of the plummer, the contact stud of the trigger bar contacts the periphery of the optical disk and rotates; a control panel is provided, which is stirred by the trigger bar to start to transport the power of the motor and move.
In the above mentioned optical disk loading final position detection device, the support part that moves together with the detection bars is located on the base plate, and it can freely move along the transport direction of the optical disk. The support part is approximately connected at the central position of the trigger bar. So, when the trigger bar contacts the periphery of the optical disk and rotates, the support part moves along the transport direction of the optical disk, to make the trigger bar to rotate around the contact part where it contacts the control panel. By the rotating of the trigger bar, the contact stud located at the front end of the trigger bar will contact the periphery of the optical disk at the position corresponding to the outer diameter of the optical disk loaded.
In the above mentioned optical disk loading final position detection device, for the detection bars will rotate for a vast scale when the optical disk of big diameter is loaded, the support part will also move for a vast scale along the transport direction of the optical disk. So, the rotary displacement of the trigger bar will get big, and the contact stud will move for a vast scale along the transport direction of the optical disk, which is not good for miniaturizing the optical disk playing device. For example, when the product casing is made to be as big as or smaller than the maximum diameter of the optical disk, then the optical disk playing device contained in the case is at least smaller than the maximum outer diameter of the optical disk. By this time, if the contact stud is made to move along the transport direction of the optical disk, the contact stud will extrude to the position out of the maximum outer diameter along the transport direction of the optical disk, which is not desirable.